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Wolf-Dieter N. Busch

Publications and source records attributed to Wolf-Dieter N. Busch.

9 recordsLinked to original sources

The effects of water levels on Two Lake Ontario Wetlands

Lake Ontario's water levels have been regulated since 1959, after the completion of the St. Lawrence River navigation and hydropower development project. The plan used to guide the regulation (1958-D) has been in effect since 1963 (Bryce, 1982). The purpose of the regulation was to prevent extreme high-water levels which increased erosion on the south shore of Lake Ontario, while protecting the interests of commercial navigation and hydropower production in the St. Lawrence River (T. Brown, personal communication, member of the Board of Control). Major user groups have sought further reductions in the range of lake level fluctuations. However, the biological resources, especially the lake influenced wetlands, benefit from the waterlevel fluctuations. Great Lakes wetlands are the most important habitat for wildlife of the region (Tilton and Schwegler, 1978). We provide information here on the responses of wetland plant communities in two wetlands to changes in lake levels over time.

Book↗

Food of forage fishes in western Lake Erie, 1975-76

In western Lake Erie in the summer and fall of 1975–1976, food eaten by seven forage fishes—emerald shiner ( Notropis atherinoides ), spottail shiner ( Notropis hudsonius ), trout-perch ( Percopsis omiscomaycus ), andyoung-of-the-year (YOY) of alewife ( Alosa pseudoharengus ), gizzard shad ( Dorosoma cepedianum ), white bass ( Morone chrysops ), and freshwater drum ( Aplodi-notus grunniens )—was divided among six major taxa: Cladocera, Copepoda, Diptera, Ostracoda, Amphipoda, and Algae. In addition, fish were eaten by YOY white bass, and Rotifera were consumed by YOY gizzard shad. Interspecies diet overlap indices, calculated to compare the food of the different species and to evaluate diet similarities, were usually highest for YOY white bass and YOY freshwater drum when compared with the other species and usually lowest between emerald shiners and all other forage fishes. Understanding the feeding interactions among fishes that could influence production at the forage-food level of the food web could provide insight into how cascading trophic interactions influence the production of piscivorous predators.

Journal of Great Lakes Research↗

Hydrological, morphometrical, and biological characteristics of the connecting rivers of the International Great Lakes: a review

The connecting channels of the Great Lakes are large rivers (1, 200-9, 900 m3 • s-1) with limited tributary drainage systems and relatively stable hydrology (about 2:1 ration of maximum to minimum flow). The rivers, from headwaters to outlet, are the St. Marys, St. Clair, Detroit, Niagara, and St. Lawrence. They share several characteristics with certain other large rivers: the fish stocks that historically congregated for spawning or feeding have been overfished, extensive channel modification have been made, and they have been used as a repository for domestic and industrial wastes and for hydroelectric energy generation. Levels of phosphorus, chlorophyll a, and particulate organic matter increase 3- to 5-fold from the St. Marys River to the St. Lawrence River. Biological communities dependent on nutrients in the water column, such as phytoplankton, periphyton, and zooplankton similarly increase progressively downstream through the system. The standing crop of emergent macrophytes is similar in all of the rivers, reflecting the relatively large nutrient pools in the sediments and atmosphere. Consequently, emergent macrophytes are an important source of organic matter (67% of total primary production) in the nutrient poor waters of the St. Marys River, whereas phytoplankton production dominates (76%) in the enriched St. Lawrence River. Submersed and emergent macrophytes and the associated periphyton are major producers of organic matter in the connecting channels. Another major source of organic matter (measured as ash free dry weight, AFDW) in the Detroit River is sewage, introduced at a rate of 26, 000 t per year. The production of benthos ranges from a low 5.4 g AFDW•m-2 in the Detroit River to a high of 15.5 g AFDW•m-2 in the St. Marys River. The rivers lack the organic transport from riparian sources upstream but receive large amounts of high quality phytoplankton and zooplankton from the Great Lakes.

Canadian Special Publication of Fisheries and Aqua↗

Decline of mercury in young fishes from western Lake Erie between 1970-71 and 1974

Concentrations of total mercury were determined for samples of age 0-II whole fish of six species collected from western Lake Erie in 1970-71 and five species collected in 1974. Within years, average total mercury concentrations increased with age and size in all species. The concentrations were significantly lower (37 to 86%) in 1974 than in 1970-71. Methylmercury concentrations and the proportion of methylmercury to total mercury increased with age and size of fish in samples of four species collected in 1970-71.

Progressive Fish-Culturist↗

Food of white perch, rock bass and yellow perch in eastern Lake Ontario

The contents of stomachs from 1,485 white perch, 218 rock bass and 1,399 yellow perch collected in eastern Lake Ontario from May to October in 1972 and in May 1973 were examined. All three species fed primarily on amphipods, but they also ate chironomids and trichopterans regularly. Rock bass ate more trichopterans than chironomids, whereas white perch and yellow perch ate more chironomids. Snails and crayfish were significant items in the diet of rock bass, but occurred infrequently in stomachs of white perch and yellow perch. White perch and yellow perch frequently ate fish eggs during early summer, but rock bass seldom ate fish eggs. Fish were important in the diets of white perch longer than 300 millimeters and rock bass and yellow perch longer than 200 millimeters. Similarities in the diets of fish 1 year old or older suggest that the potential for competition between white perch and yellow perch is greater than that between rock bass and either white perch or yellow perch.

New York Fish and Game Journal↗

Establishment of white perch, Morone americana , in Lake Erie

White perch, Morone americana, was first reported in Lake Erie in 1953. No further reports of capture were recorded until 1973, when one fish was taken. Three other captures were confirmed in 1974, and 34 in 1975. All but 3 of the 38 specimens were taken in the warm, shallow western basin and the extreme eastern end of the central basin. The widespread distribution and the sizable numbers of specimens collected in 1975 strongly indicate that this nonendemic species has become established in Lake Erie.

Journal of the Fisheries Research Board of Canada↗

Environmental factors affecting the strength of walleye ( Stizostedion vitreum vitreum ) year-classes in western Lake Erie, 1960-70

Commercial production of walleyes ( Stizostedion vitreum vitreum ) from western Lake Erie declined from 5.9 million pounds in 1956 to 140,000 pounds by 1969. Since 1956, marked irregularity in year-class success has developed. Only four year-classes were considered good during 1959–70. The rate and regularity of water warming during the spring spawning and incubation periods in 1960–70 had a positive effect on the density of egg deposits and the resulting year-class strength. Rates of warming were not themselves detrimental, but rather the extended length of the incubation period in cool springs increased the exposure of eggs to such negative influences as dislodgment from the spawning reefs by strong current action generated by spring storms, or siltation and low oxygen tensions. The annual brood stock size had much less influence on year-class strength than did water temperature. Reproductive success was unrelated to fluctuations in size of suitable reef spawning area caused by changes in water level. Apparently the usable spawning area at any water level is more than adequate to serve the limited walleye brood stocks.

Journal of the Fisheries Research Board of Canada↗

Predation by fish on walleye eggs on a spawning reef in western Lake Erie, 1969-71

Nearly 2,000 fish representing 21 species were captured with experimental gillnets on Kelleys Island Shoal during the spawning and incubation periods of walleyes (Stizostedion v. vitreum) in 1969-71. A total of 794 stomachs were examined. Four species contained walleye eggs: yellow perch (Perca flavescens), spottail shiner (Notropis hudsonius), stonecat (Noturus flavus) and white sucker (Catostomus commersoni). Yellow perch were by far the most consistent predators of walleye eggs, and spent female perch consumed more eggs than did males. The average number of walleye eggs in perch stomachs collected on any one day ranged from 36 to 734 for females and from 4 to 237 for males. The loss of walleye eggs due to fish predation appeared to be significant only when the rate of water warming slowed or stopped, thereby creating an extended overlap in the walleye-yellow perch reproductive period. Only under the uncommon condition of an extended time interval between walleye hatching and perch spawning, coupled with the presence of a large quantity of actively feeding perch, could egg predation reduce walleye reproductive success.

Ohio Journal of Science↗